1. Field of the Invention
The present invention relates to a single-lens reflex camera with a collapsible lens and, more particularly, to a single-lens reflex camera in which a part of the photo-taking lens is retracted in a mirror box space evacuated by a reflex mirror so that the camera can be made compact when it is not used.
2. Description of the Related Art
A single-collapsible-lens reflex camera is disclosed in Japanese Unexamined Patent Publication No. 2-109338, in which a reflex mirror is raised at the same time a main switch is turned OFF, thereby permitting the lens to be collapsed in the mirror box.
In an exposure sequence as used in general single-lens reflex cameras, shutter curtains are first spring-charged and then arrested by mechanical arresting members. The shutter curtains are next electrically held by energizing shutter-curtain holding electromagnets in response to a release signal, and the shutter curtains are then released from being mechanically arrested and held only electrically after mirror up is started. The electromagnets are deenergized at a predetermined time to thereby cause the shutter curtains to run. In collapsing the lens in the camera body in such single-lens reflex cameras, if the shutter is kept charged, then the electromagnets will be energized unnecessarily, leading to a waste of power. If the mirror is raised prior to the collapse of the lens, the leading and following curtains will be caused to run rapidly by spring force when the mechanical arresting members are released. A noise made at that time would cause the camera user to make a mistake of judging that the shutter was released or would give the user an unpleasant feeling.